Depo shot or something else

Alexis • Mom of a little girl ❤️ Aubree Elizabeth Dellinger was born 9/1/28
I was on the depo shot before and I got pregnant. Never did I spot on it. Well I'm on it again. Got it done in march and I have been spotting every month. Today I was spotting with light cramps. Could it have been the depo or pregnant